Bihejvioralna odbrana sjeničko-pešterskog ekotipa medonosne pčele od krpelja Varroa destructor

Two behaviours of honey bees, hygienic and grooming, are mechanisms of defense against brood diseases and parasitic mites, including Varroa destructor. Apis mellifera colonies remove the worker brood infested with Varroa destructor mites from the nest (hygienic behaviour), and groom the mites off other adult bees (grooming behaviour). In this study hygienic and grooming behaviours of Sjeničko-Pešterski honey bee ecotype were analysed in 440 honey bee colonies from 11 localities in the region of Sjeničko-Pešterski plateau, Podpešterje, Golija Mt. and Rogozna ML At each locality 40 honey bee colonies were investigated: 10 potent colonies with one-year old queen, 10 potent colonies with two-year old queen, 10 medium potent and 10 weak honey bee colonies. Hygienic behaviour was expressed in a range from 95.12% to 99.50% in potent honey bee colonies with one-year old and two-year old queens. Statistically highly significant (p lt 0.01) differences were registered among the analysed honey bee colonies at the investigated region, in favour of the potent honey bee colonies, compared to the medium potent and weak colonies. Also, statistically highly significant (p lt 0.01) differences were recorded between potent colonies with one-year old queens and colonies with two-year old queens, in favour of the colonies with one-year old queens. In general, investigated colonies belong to a category of the so called "hygienic colonies", as the efficiency of elimination of damaged pupae amounted to 91.50%. Grooming behaviour of Sjeničko-Pešterski honey bee ecotype potentially exists, but its significance cannot be discussed as, on the whole, investigated colonies showed potential of 34,04%. Our results point to an indisputable relationship between analysed behaviours and the strength of honey bee colonies: hygienic behaviour is more expressed in potent colonies (from 95.12% to 99.50%) regardless of queen age; grooming behaviour was expressed only in potent honey bee colonies with one-year old queen at all 11 localities, where the number of damaged mites ranged from 36,05% to 39,61%. The damaged mites were separated into six categories. The most frequent category of damage was damaged legs (53.38% in potent colonies with one-year old queens and 52.02% in potent colonies with two-year old queens). The potent honey bee colonies from the investigated region especially with one-year old queen, could be used for highly selected breeds improving and queens rearing.Higijensko i negovateljsko ponašanje predstavljaju dva mehanizma odbrane od bolesti legla i parazitskih krpelja, uključujući Varroa destructor. Društva Apis mellifera uklanjaju iz satnih ćelija radiličko leglo infestirano krpeljima Varroa destructor (higijensko ponašanje) i skidaju krpelje sa adultnih pčela (negovateljsko ponašanje). U ovom radu, obavljena je analiza higijenskog i negovateljskog ponašanja pčela sjeničko-pešterskog ekotipa kod ukupno 440 pčelinjih društava sa 11 lokaliteta Sjeničko-Pešterske visoravni Podpešterja, Golije i Rogozne. Na svakom lokalitetu ispitivano je 40 pčelinjih društava: 10 jakih društava sa jednogodišnjom maticom, 10 jakih društava sa dvogodišnjom maticom, 10 srednje jakih i 10 slabih pčelinjih zajednica. Higijensko ponašanje bilo je ispoljeno u opsegu od 95,12% do 99,50% kod jakih pčelinjih zajednica sa jednogodišnjim i dvogodišnjim maticama. Između ispitivanih pčelinjih društava pomenutog područja registrovane su statistički visoko značajne razlike (p lt 0.01) u ispoljenosti higijenskog ponašanja u korist jakih pčelinjih zajednica u odnosu na srednje jake i slabe. Takođe, visoko značajne razlike (p lt 0.01) u ispoljenosti ove osobine zabeležene su i između pčelinjih zajednica sa jednogodišnjim i dvogodišnjim maticama, u korist pčelinjih zajednica sa jednogodišnjim maticama. Generalno, pčelinja društva sa analiziranog područja Sjeničko-Pešterske visoravni, Podpešterja, Golije i Rogozne pripadaju kategoriji higijenskih društava, obzirom da je prosečna efikasnost eliminacije oštećenih lutki svih zajednica iznosila 91,50%. Negovateljsko ponašanje kod pčela sjeničko-pešterskog ekotipa potencijalno postoji, ali se ne može govoriti o izraženosti ove osobine, obzirom da je globalna sposobnost eliminacije krpelja sa oštećenjima u ukupnom broju odbačenih krpelja svih ispitivanih pčelinjih zajednica bila 34,04%. Ovi rezultati ukazuju na postojanje neosporne povezanosti analiziranih oblika ponašanja i jačine pčelinje zajednice: higijensko ponašanje je vise ispoljeno kod jakih društava (od 95.12% do 99,50%) nezavisno od starosti matice, dok je negovateljsko ponašanje bilo izraženo samo kod pčelinjih zajednica iz kategorije jakih društava sa jednogodišnjom maticom na svim lokalitetima (od 36,05% do 39,61 % oštećenih krpelja u odnosu na celokupan uzorak). Oštećeni krpelji su podeljeni u 6 kategorija. Najčešći tip oštećenja predstavljaju oštećene noge (53.38% u jakim društvima sa jednogodišnjom maticom i 52.02% kod jakih društava sa dvogodišnjom maticom). Jaka pčelinja društva sa ispitivanog područja, i to naročito ona sa jednogodišnjom maticom, mogu koristiti za poboljšanje visoko selekcionisanih sojeva, kao i u proizvodnji selekcionisanih matica sa izraženim higijenskim i negovateljskim ponašanjem

Ispitivanje genotoksičnosti 8-CI-cAMP u dva in vivo testa na miševima soja BALB/c

The antitumor agent 8-CI-cAMP (8-chloro-cyclic adenosine monophosphate) is the most potent site-selective analogue of cAMP. It acts primarily by selective down-regulation of regulatory sub-units of cAMP-dependent protein kinases. This results in reversion of the neoplastic predominance of PK-I type over PK-II type protein kinase back to the ratio more typical to of the normal phenotype. The differential activity of 8-CI-cAMP towards protein kinase isozymes leads to inhibition of cell growth, differentiation and neoplastic reversion of a wide variety of cancer cell lines. Since 8-CI-cAMP has been investigated as a new potential anticancer drug with no previous studies of its mutagenic and clastogenic effects, we have investigated the genotoxicity of 8-CI-cAMP. Genotoxic effects were estimated by the bone marrow micronucleus assay and the occurrence of morphological chromosome lesions in adult mice (BALB/c strain). 8-CI-cAMP was administered intraperitoneally (i.p) in three doses, 10 mg/kg b.w.; 90 mg/kg b.w. and 160 mg/kg b.w., with saline solution as a negative control and cyclophosphamide, a known mutagen and clastogen as a positive control at twenty four hour intervals during a seven day period. Micronucleus test results showed a consistent dose-dependent pattern. Thus, with increase of the dose (10 mg/kg b.w., 90 mg/kg b. w. and 160 mg/kg b.w.) there was an increase in the frequency of micronuclei in polychromatic erythrocytes (4.88 ± 0.35; 8.32 ± 0.57; 11.75 ± 0.37) compared to the negative control (2.04 ±0.28). Using chromosome aberrations as an indicator of genotoxic potential, 8-CI-cAMP in all three doses (10 mg/kg b.w.; 90 mg/kg b.w. and 160 mg/kg b.w.) produced karyotype transformation of mouse bone marrow cells. 8-CI-cAMP induced structural chromosome aberrations as lesions (2.87 0.14; 4,37 0.14 i 5.25 0.35), interruptions (9±0.1; 12.37±0.26 i 13.37±0,33), ring chromosomes (3.62 0.21; 2.5±0,07 i 2.5±0.07), accentrics (10±0.49; 16.5±0.45 i 18.37±0.54) and Robertsonian translocations (7.12±0.26 ;9 0.1 i 11.24 ±0.18) as well as numerical chromosome aberrations of the aneuploidal type (36 5± 0.74; 60.25±0.24 i 85.62±0.5) and polyploidy (7±0.24; 5.5+0.27 / 5.87±0.14). These results demonstrate the genotoxic potential of the investigated substance.Antitumorski preparat 8-CI-cAMP (8-hloro-ciklični adenozin monofosfat) je najpotentniji analog AMP koji deluje primamo na modulaciju cAMP - zavisne protein kinaze dovodeći do inhibicije regulatornih subjedinica. Rezultat takvog dejstva je smanjenje dominantnog tipa PK-I protein kinaze u kanceroznim ćelijama nad drugim tipom PK-II protein kinaze, u odnosu na međusobni nivo PK-I I PK-II koji se nalaze u normalnim ćelijama. Ciklični 8-CI-AMP je analog koji ima izuzetnu anti-neoplastičnu aktivnost sa efektom restauracije, diferencijacije i reverzne transformacije kanceroznih ćelija miša i čoveka. Sa stanovišta mogućeg mutagenog i genotoksičnog efekta 8-CI-cAMP nije dovoljno istražen. Zato je i cilj ovog rada bio da se primenom citogenetičkog i mikronukleus testa, na ćelijama kostne srži miša BALB/c soja, ispita genotoksični efekat 8-CI-cAMP u tri dozna režima (10 mg/kg t.m; 90 mg/kg t.m. i 160 mg/kg t.m.). Pored eksperimentalnih grupa životinja u eksperimentu su uspostavljene i negativna kontrola koju su činile jedinke tretirane sa fiziološkim rastvorom, kao i pozitivna kontrola životinja koje su tretirane sa poznatim klastogenom i mutagenom-ciklofosfamidom u dozi od 40 mg/kg t.m. Rezultati ispitivanja pokazuju konzistetni dozno-zavisni obrazac primenom mikronukleus testa. Sa rastom doze (10 mg/kg t.m ; 90 mg/kg t.m. i 160 mg/kg t.m.) raste i broj mikronukleusa u polihromatofilnim eritrocitima (4,88 ±0,35; 8,32±0,57; 11,75±0,37) u odnosu na kontrolnu grupu (2,04±0,28). Testirane rastuće doze 8-CI-cAMP u citogenetičkom testu in vivo pokazuju sposobnost transformacije kariotipa ćelija kostne srži BALB/c miševa u vidu struktumih hromozomskih aberacija tipa lezija (2,87±0,14; 4,37±0,14; 5,25±0,35), prekida (90,1; 12,37±0,26; 13,37±0,33), ring hromozoma (3,62+0,21; 2,5±0,07; 2,5±0,07), acentrika (100,49; 16,5±0,45; 18,37±0,54) i Robersonovih translokacija (7,12±0,26; 90,1; 11,24±0,18) i numeričkih hromozomskih aberacija tipa aneuploidija (36,5±0,74; 60,25±0,24; 85,62±0,5) i poliploidija (70,24; 5,5±0,21; 5,87±0,14) što ukazuje na postojanje genotoksičnog potencijala ispitivane supstance

Dietary conjugated linoleic acid influences the content of stearinic acid in porcine adipose tissue

The present study was conducted in order to determine the effects of supplementation of a growing-finishing pig diet with 0.5% conjugated linoleic acid (CLA) on production characteristics and slaughter traits. Ninety-seven female Swedish Landrace pigs were used. The control group of animals was fed a regular diet (n = 49), while the experimental group of animals (n = 48) received a diet where part of the soybean oil was substituted with commercially enriched CLA oil (containing at least 56% of CLA isomers, 28% cis-9, trans-11 and 28% trans-10, cis-12). The experiment lasted 44 days; porkers were fed from an initial weight of 66.0 up until a final weight of 103.5 kg. Feed conversion ratio, carcass and ham weight, percentage of lean meat and subcutaneous fat tissue as well as intramuscular fat were recorded. The fatty acid content of ham intramuscular fat tissue was determined by HPLC. No statistically significant influence of CLA was observed, either on carcass and ham weight, or on fat percentage in subcutaneous and intramuscular tissue. Dietary CLA enrichment proved to increase the content of stearinic acid in intramuscular fat tissue, 17.29 13.26 % in experimental and 15.87 33.71 % in control group of pigs (P < 0.01). The obtained production results show no statistically significant changes in main production traits between the two groups of animals. The observed difference in the content of stearinic acid (P < 0.01) implies firmer fat tissue, which has a practical value in pig bacon fattening

Resistance to erythromycin of Campylobacter jejuni and Campylobacter coli isolated from animals and humans

The sensititivity of thermophilic Campylobacter strains isolated from caecum of broiler chickens as well as caecum and colon of pigs and human stools, were tested against erythromycin. In 16 strains isolated in broiler chickens, resistance rate was found to be 12.50%. Three of 10 strains of Campylobacter jejuni and one of 6 strains of Campylobacter coli isolated from broiler chickens were resistant to erythromycin. In 15 strains of thermophilic Campylobacters isolated from pigs, resistance rate to erythromycin was 40.00%. Resistance was exhibited more often in C. coli (50.00%) as compared to C. jejuni (20.00%). In 24 strains isolated from humans, resistance was demonstrated at the rate of 12.50%. Out of 17 strains of C. jejuni isolated from humans, resistance was exhibited in 17.65% strains. None of 7 strains of C. coli isolated from humans exhibited resistance to erythromycin. Thermophilic campylobacters, especially C. coli isolated from pigs were more resistant to erythromycin than strains isolated from humans and broiler chickens. Therefore, a great attention should be directed to the macrolides monitoring in swine farming in order to prevent resistance in animals and its subsequent spread to human

Prevalencija gastrointestinalnih helminata kod teladi u zapadnoj Srbiji

This study was undertaken to estimate the prevalence of gastrointestinal helminths in calves in western Serbia. Throughout 2011 faecal samples were collected from 600 calves aged up to 180 days, samples were examined with the flotation method and a modified McMaster technique. The parasitizing helminth species were identified and the level of infection compared between different age groups. As many as 64.17% animals were found to be infected. The following parasite species were diagnosed: Moniezia spp. (3.17%), Toxocara vitulorum (35.00%), Strongyloides papillosus (34.50%), gastrointestinal strongyles (4.50%) and Trichuris discolor (2.17%). The majority of calves were infected with two, fewer with three or one helminth species, and the smollest number of calves harboured four parasite species. The prevalence of established helminth infections varied depending on the calves' age.Studija je sprovedena sa ciljem da se utvrdi prevalencija gastrointestinalnih helminata kod teladi u zapadnom delu Srbije. Tokom 2011. godine prikupljeni su uzorci fecesa ukupno 600 teladi starosti do 180 dana. Uzorci su pregledani metodom flotacije i modifikovanom metodom po McMasteru. Determinisane su vrste helminata i određena je prevalencija infekcije kod teladi različite starosti. Rezultati ispitivanja pokazali su da je infekcija helmintima bila prisutna kod 64,17% pregledanih životinja. Ustanovljene su sledeće vrste helminata: Moniezia spp. (3,17%), Toxocara vitulorum (35,00%), Strongyloides papillosus (34,50%), želudačnocrevne strongilide (4,50%) i Trichuris discolor (2,17%). Većina teladi istovremeno je bila inficirana dvema vrstama, zatim sa tri i jednom vrstom helminta, dok je kod samo nekoliko životinja bilo ustanovljeno prisustvo četiri vrste ili grupe helminata. Prevalencija infekcija helmintima razlikovala se kod teladi različite starosti

Optimizacija parametara sinterovanja debeloslojnih otpornika na bazi Bi2Ru2O7 slojne otpornosti 10 kΩ/sq

Razvoj novih i unapređenje postojećih elektronskih komponenti koje doprinose smanjenju po-trošnje električne energije pogoduju prelasku sa tradicionalnih na obnovljive izvore energije i doprinoseenergetskoj efikasnosti. Debeloslojni otpornici su pasivne komponente koje se sve više kor-iste u pametnim energetski štedljivim kućnim uređjima, LED osvetljenju, upravljanju klima uređajima, električnim trotinetima, sistemima za upravljanje baterijama itd. Zbog toga će u ovom radu biti reči o uticaju parametara sinterovanja na formiranje strukture najčešće korišćenih debe-loslojnih otpornika na bazi Bi2Ru2O7slojne otpornosti 10 kΩ/☐.Development of new and improvement of existing energy-saving electronic components are supporting transition from traditional to renewable energy sources and contributing to energy effi-ciency. Thick-film resistors are passive components that are often being used in energy-saving smart home appliances, LED lighting, air conditioning management, electric scooters, battery management systemsetc. For these reasons, this paper will deal with optimization of 10 kΩ/sq Bi2Ru2O7thick-film resistors sintering parameters.The 10th ICREPS was held on October 17 and 18, 2022, in Chamber of Commerce and Industry, of Serbia, Belgrade

Investigations of genotoxic potential of levamisole hydrochloride in bone marrow cells of Wistar rats

An experiment was performed under in vivo conditions on bone marrow cells of Wistar rats. The following doses of levamisole hydrochloride were tested: a therapeutic dose of 2.2 mg/kg bm, a dose of 4.4 mg/kg bm, LD50 -25% mg/kg bm, and LD50 -75% mg/kg bm. We followed the effect of levamisole hydrochloride on kinetics of the cell cycle and the appearance of structural and numeric changes in chromosomes in bone marrow cells. The therapeutic dose of levamisole of 2.2 mg/kg bm exhibited a capability to increase mitotic activity in the observed cells, thus confirming knowledge of the immunostimulative effect of this dose of the medicine under in vivo conditions. The other tested doses of levamisole in this experiment, observed in comparison with the control group, had an opposite effect, namely, they caused a reduction in the mitotic activity of bone marrow cells. All the examined doses in vivo exhibited the ability to induce numeric (aneuploid and polyploid) and structural (lesions, breaks and insertions) chromosomal aberrations. It can be concluded on the grounds of these findings that the examined doses have a genotoxic effect

Data handling culture – a forgotten aspect of the integration of renewable electrical power sources

Trenutni trendovi poput digitalizacije, digitalne transformacije, industrije 4.0 i sličnog, koji su karakteristika savremenog društva u celini, nametnuli su svet podataka kao imperativ svih sfera ljudskog delovanja. U vrlo kratkom vremenskom roku probijene su sve ranije pretpostavljane barijere u trenutnoj količini podataka koja je u opticaju na globalnom nivou i koja se trenutno meri u desetinama zetabajta sa tendencijom kontinuiranog uvećanja u godinama koje slede. Trend povećanja količine podataka može se zabeležiti na svim nivoima, bez obzira da li posmatramo neki manji, lokalizovani uzorak, regionalni uzorak, ili, kao što je već navedeno, posmatramo globalni digitalni svet. Čak i ako nivo posmatranja svedemo na pojedinačnu instancu, gotovo da nema slučaja u kome ne možemo identifikovati neko povećanje količine podataka. Proporcionalno povećanju količine podataka, uvećala se i potrebna energija koju na različitim nivoima treba obezbediti za neku preduzetu radnju nad tim podacima, bilo da se radi o samom kreiranju tih podataka, skladištenju istih, nekoj vrsti obrade, umnožavanju ili nekoj drugoj adekvatnoj vrsti radnje nad tim podacima. Procenjuje se da već nekoliko procenata celokupne svetske proizvodnje električne energije odlazi na segment obezbeđenja neophodnih uslova za izvršenje neke od radnji nad podacima. U skladu sa tim, mnogi veliki centri za rukovanje podacima parcijalno ili u celosti prelaze na sisteme zasnovane na upotrebi obnovljivih izvora električne energije. Iako je taj transfer doneo niz prednosti i dalje postoji problem ekspanzije podataka na jednom dugoročnijem planu koji nova energetska rešenja treba da isprate. U radu će se pokazati kako se jednim racionalnijim rukovanjem podacima na različitim nivoima upotrebe može stvoriti daleko povoljnije energetsko okruženje na globalnom nivou i kako to okruženje može doprineti jednoj održivosti trenutno primenjenih rešenja koji se tiču upotrebe obnovljivih izvora električne energije u različitim segmentima upotrebe i rada sa podacima u modernom okruženju.Current trends such as digitalization, digital transformation, Industry 4.0 and the like, which are characteristic of modern society as a whole, have imposed the world of data as an imperative of all spheres of human activity. In a very short period of time, all previously assumed barriers in the current amount of data in circulation at the global level, which is currently measured in tens of zettabytes with a tendency to continuously increase in the years to come, have been exceeded. Even if we reduce the level of observation to a single instance, there is almost no case in which we cannot identify any increase in the amount of data. In proportion to the increase in the amount of data, the required energy that needs to be provided at different levels for any action taken on this data has increased, whether it is the creation of this data, its storage, some processing, replication or some other adequate type of action. It is estimated that already few percents of the entire world production of electricity go to the segment of providing the necessary conditions for the performance of some of the work on data. Accordingly, many large data centers are partially or completely switching to systems based on the use of renewable energy sources. Although this transfer has brought a number of advantages, there is still the problem of data expansion in a long-term plan that new energy solutions need to follow. The paper will show how a more rational data handling at different levels of use can create a far more favorable energy environment at the global level and how this environment can contribute to the sustainability of currently applied solutions for renewable energy in different segments of use and work with data in a modern environment.The 10th ICREPS was held on October 17 and 18, 2022, in Chamber of Commerce and Industry, of Serbia, Belgrade

Ispitivanje genotoksičnog efekta Carbadoxa in vitro i in vivo

Due to its bactericidal activity Carbadox is used for treatment of swine dysentery and salmonellosis. Also, it can be used as a factor for growth stimulation. Carbadox is the only drug for certain health problems in swine production. At the same time Carbadox is slowly metabolized. The aim of this work was an examination of Carbadox genotoxicity in vivo and in vitro. In vitro genotoxicity of different doses of Carbadox was examined on cultured human peripheral blood lymphocytes. Damage to chromosomal DNA was observed under the microscope as sister chromatid exchanges (SCEs). In vivo genotoxicity of Carbadox was examined on metaphase chromosomes from bone marrow cells of BALB/c strain male mice. Experimental animals were intragastrically treated with three different doses of Carbadox. In addition there were negative and a positive control groups of mice. Animals in the positive control were treated with a known clastogenic agent, cyclophosphamide, in a dose of 0,4 mg/kg b.w. In vivo genotoxicity of Carbadox was examined through eight experimental cycles. The results showed that this preparation with an antimicrobial mode of action induced damage to chromosomal DNA in human lymphocytes as well as structural and numerical chromosomal changes in bone marrow cells of BALB/c mice. All the examined concentrations of Carbadox significantly increased SCEs and consistently manifested a dose-dependent pattern. Also, all the examined doses caused karyotypic changes in vivo inducing numerical and structural chromosomal aberrations in mouse bone marrow cells. There was a positive correlation between the number of bone marrow cells with cytogenetic changes and the dose of Carbadox. It could be concluded that Carbadox expressed potential genotoxicity, especially at the highest investigated doses.Carbadox je sintetsko organsko jedinjenje (Metil-3(2quinoksal-metilen) karbozat-N1-N4 dioksid) sa baktericidnim dejstvom koje se koristi u suzbijanju svinjske dizenterije i salmoneloze i kao faktor koji stimuliše rast. Zbog spore metaboličke obrade i dugog zadržavanja u organizmu tretiranih životinja, a još vise zbog njegovog toksičnog, citotoksičnog i kancerogenog dejstva, Carbadox u novije vreme predmet detaljnih proučavanja. U ovom radu su izneti rezultati in vitro ispitivanja efekta Carbadoxa na limfocite periferne krvi čoveka praćenjem promena na nivou molekula DNK na osnovu učestalosti razmene sestrinskih hromatida. Citogenetička ispitivanja uticaja Carbadoxa, posle intragastrične aplikacije, na nastanak hromozomskih promena u ćelijama kostne srži obavljena su na miševima BALB/c soja. Hromozomi za kariotipsku analizu su dobijeni korišćenjem direktne metode ispiranja srži dugih cevastih kostiju. Rezultati ispitivanja efekata različitih doza Carbadoxa in vitro na limfocitima čoveka i in vivo na ćelijama kostne srži miševa BALB/c ukazali su da ovaj antibiotik poseduje visok genotoksični potencijal i jasno manifestuje mutageni efekat

RuO2/Bi2Ru2O7 thick-film strain sensor with low temperature sensitivity

Structural health monitoring that gathers information about performance and conditions of civil engineering structures requires implementation of sensor networks that include strain sensing devices. This paper introduces RuO2/Bi2Ru2O7 thick-film strain sensor with low-temperature sensitivity. Under strain, RuO2/Bi2Ru2O7 thick resistive film experiences reversible deformation that can be registered as a change in film resistivity. Based on that effect, a prototype of the strain sensor is being realized and evaluated. Evaluation included measurements of the resistance change under applied strain, determination of the gage factor and investigations of and thermal stability.ISPC «Modern information and electronic technologies» : May 23-27, Odes